This proposal from the Biomedical Magnetic Resonance Laboratory (BMRL) at Washington University in St. Louis requests funds to purchase a Varian NMR Systems MRI scanner console and a Magnex Scientific magnetic field gradient/shim system. These items will be combined with a 4.7T (200 MHz) Oxford Instruments 33-cm bore magnet, which is currently on-hand, to form a state-of-the-art MRI scanner. The scanner will be administered through the BMRL, which supports resources at the forefront of in vivo MR imaging science through its 4.7- and 11.74-T small-animal scanners located at the Medical School campus. There is a pressing need within the BMRL user community for a scanner committed to experiments that are not in vivo. These include: (i) RF coil design and testing, (ii) pulse sequence design, implementation, and validation using phantom/test objects, (iii) lengthy imaging sessions, lasting many hours or more, involving ex vivo tissue samples (e.g., heart, brain, spinal cord), and (iv) user training in scanner operation. These categories of scanner usage are critical for the ultimate success of in vivo studies and must be pursued, yet these pursuits consume scanner time that is urgently needed for in vivo experiments. The requested scanner will fill this need. Further, the scanner will be sited in the heart of the University's physics and engineering complex, enabling this physical sciences community to more effectively engage in biomedical MRI studies. This proposal provides documentation of: need, past imaging performance, organizational and training competence, and institutional commitment.